Forging presses

ABSTRACT

An upsetting for forging machine having at least one pair of relatively movable dies, one of which is arranged to carry out a circular rocking motion about a point related to the centre of one of the dies of the die set, the other die including at least one linearly movable element in order that the die can be moved towards or away from the rockable die, there being a ram means associated with the linearly movable die in order that a workpiece after upsetting or forging can be ejected from the die set.

United States Patent [191 Foster et al.

[ FORGING PRESSES [75] inventors: John Foster; Geoffrey Wilson, both of Denton, England [73] Assignee: B & S Massey Limited [22] Filed: Nov. 10, 1972 [21] Appl. No.: 305,643

Related US. Application Data [62] Division of Ser. No. 51,536, July 1, 1970, Pat. No.

[52] US. Cl 72/67, 29/1567 C, 72/418, 72/432 [51] Int. Cl. B2lj 9/12, B21j 13/02, B21f 5/00 [58] Field of Search 72/125, 318, 418, 308,

[56] References Cited UNITED STATES PATENTS 1,359,625 11/1920 Slick 1,970,134 8/1934 Ferris 72/427 Mar. 26, 1974 1,983,618 12/1934 Lamond 73/318 2,442,142 5/1948 Nettenstrom 72/318 3,299,453 1/1967 Van de Meerendonk... 72/427 3,483,726 12/1969 Burke et a1. 72/427 3,494,161 2/1970 Silichev 72/429 3,703,823 11/1972 Wilson 72/406 Primary Examiner-Charles W. Lanham R Assistant Examiner-Joseph A. Walkowski ifttorr iey, Agent, 6FF ir m- Alanmeyineifireitenfeld & Levine [5 7] ABSTRACT An upsetting for forging machine having at least one pair of relatively movable dies, one of which is arranged to carry out a circular rocking motion about a point related to the centre of one of the dies of the die set, the other die including at least one linearly movable element in order that the die can be moved towards or away from the rockable die, there being a ram means associated with the linearly movable die in order that a workpiece after upsetting or forging can be ejected from the die set.

10 Claims, 8 Drawing Figures PATENIED R25 1874 SHEET 3 0F 6 PATENT E0 was m4 SHEU 5 0F 6 PATENTEDIIARZS 1914 3798944 SHEET 6 0F 6 FORGING PRESSES This application is a division of application Ser. No. 51,536 now US. Pat. No. 3,733,884.

This invention concerns upsetting or forging machines.

The invention refers particularly though not exclusively to upsetting or forging machines for upsetting or forging, forming or rolling circular or other shaped objects of regular or irregular form.

In upsetting or forging machines of the generally known kinds the total surface of the article or object is operated upon simultaneously with the result that very high peak loads are produced necessitating extremely strong, heavy and consequently expensive machines. A further difficulty experienced in upsetting or forging machines, particularly when producing forgings from tube or bar stock, lies in the inability to gather or upset the material for the forging without bending or otherwise deforming the stock and thus creating fault lines in the finished forging. It has been generally considered that there is a practical limit to the amount of metal which can be upset and that this limit bears a direct relationship to the ratio between the length and the diameter of the stock. The generally accepted length to diameter ratio between which it is possible to produce forgings without fault lines is 3:1 and above this it is accepted that the possibility of efficient operation does not exist due to the risk of bending or otherwise deforming the stock.

The primary object of the present invention is to provide an upsetting or forging machine in which the above mentioned disadvantages are overcome or at least substantially reduced.

It has previously been proposed by the applicants to provide an upsetting or forging machine in which the dies are so formed and the motion of the machine is so contrived that different parts of the dies come successively into operation so as to ensure that sufficient pressure is created only between the operative parts of the disc to enable the material of the workpiece to be manipulated to create the desired form in the workpiece.

It is therefore a further object of the present invention to provide in an upsetting or forging machine the ability to operate the machine in such a manner that the maximum pressure required to create the forging is substantially less than that which will be required to produce the identical forging in a machine in which the whole of the surface of the workpiece is subjected simultaneously to pressure.

According to the present invention an upsetting or forging machine including a pair of relatively movable dies between which a workpiece or a part thereof may be located there being a workpiece receiving die formed from one or more linearly movable elements adapted to be controlled individually, collectively or in groups before or during upsetting or forging, a means for ejecting a finished workpiece from the die, and a co-operating die adapted to carry out a circular rocking motion about a point at or near the centre of one of the dies whereby a complete upsetting or forging operation may be carried out by the one pair of dies.

Preferably the machine includes a workpiece receiving die formed of a plurality of die elements in which the elements are each controllable as to their sequence and rate of movement, the direction of movement and their distance moved.

In one form the workpiece receiving die is composed of a series of concentric elements.

In a modification the workpiece receiving die is of unitary construction and is mounted upon a linearly movable contral element, the die and the control element being provided with a through bore adapted to receive a bar or tube stock workpiece, means being provided for advancing the workpiece as upsetting or forging takes place.

In a further modification the workpiece receiving die is of unitary form and is mounted upon a control element there being a co-operating die adapted to carry out a circular rocking motion and simultaneously be advanced towards the workpiece receiving die, the latter and the control element being bored to receive a bar or tube stock workpiece and means being provided to advance the workpiece as upsetting or forging takes place.

The invention will now be described further, by way of example only with reference to several practical forms thereof and the accompanying drawings in which:

FIG. 1 is a diagrammatic sectional elevation of part of one form of die and operating mechanism;

FIG. 2 is a view similar to FIG. 1 of a modification of the apparatus;

FIG. 3 is a more detailed view of part of the apparatus of FIG. 2;

FIG. 4 is a view similar to FIG. 1 of a further modification;

FIG. 5 is a schematic view of a further modification; and

FIGS. 6, 7 and 8 are schematic views showing a means of operating a machine having a die and operating mechanism similar to anyone of those illustrated in FIG. 1 to 5.

In the following description reference is made only to that part of the machine directly concerned with one die part, the remaining parts of the machine being either of generally known or proposed form and thus reference in detail to such parts is not considered to be necessary for a clear understanding of the operation of the machine. It is pointed out however, that the apparatus to be described below is particularly suited for controlling a die part in such manner as to give to that part a circular rocking motion about a point at or near the centre of the rocking die. Such an arrangement is disclosed in our co-pending application for the grant of letters Patent filed July 1, 1970 under number 51,537.

Referring now to FIG. 1 there is provided a die set comprising a die 10 adapted to perform a circular rocking motion about a point at or near the centre of that die. A second die 11 is provided and this consists of an outer portion, in the case being described having a recess l2 and a centrally disposed through hole 13. This die is either formed integrally upon the upper surface of a ram 14 or is attached to that ram. In either case the die stands proud of a flange 15 of the ram 14. The ram 14 extends through a bore 16 in the bolster 17 of the machine and the flange 15 is provided with a pair of jack rams 18 located at diametrically opposed positions on the flange 15. The jack rams are mounted in cylinders 19 in the bolster and are provided with fluid supply lines (not shown) by means of which operating fluid can be pumped to the cylinders to move the jack rams, and thus the die 1 l rapidly towards the die 10. The ram 14 is in this specification referred to as the main ram.

At the end of the main ram 14 is a cylinder 20 to which fluid lines 20a 20b are provided so that fluid can be pumped to either side of the ram piston 21 located therein so that the main ram can be moved under operating pressure towards the die during upsetting or forging of a workpiece 22 located in the die 11. In the drawing the workpiece 22 is shown finished and ready for ejection. The main ram is provided with a through bore located axially thereof and within this is located a second ram 23 the piston 24 of which is located in a cylinder 25 located at a position more remote from the die 10 that the cylinder 20 of the main ram 14. Fluid lines 25a and 25b are provided to the cylinder 25 of the second ram both above and below the piston 24 to enable the second ram to be moved into and out of the die 11. The top of the second ram, or a replaceable head piece attached thereto forms effectively a second die part and in the case in point is located in the base region of the through bore 13 of the die 11.

The second ram 23 is provided with a through bore, as is the cylinder 25 and through this passes an ejector ram 26 having a piston 27 located in a cylinder 28. This cylinder is provided with fluid lines 28a and 28b in order that fluid can be pumped to either side of the piston 27. The piston 27 is provided with a stem extending from the face opposite to the ram and this passes through the cylinder 28 into a hole 29 in the bolster 17 when the piston is retracted relative to the die 11. Adjacent this hole 29 is a stop member 30 connected to the ram of a piston 31. The arrangement is such that when the piston 27 is advanced relative to the die 11 the stem is moved from the hole 29 and the stop member 30 can be moved across the hole to prevent the piston 27 being retracted relative to the die 11. Ejection of a finished workpiece 22 is thus possible as the main ram 14 is retracted relative to the die 10. If desired the vertical position of the stop member 30 may be adjustable, for example by providing, within the bolster 17, a vertically adjustable and lockable column indicated generally by the member 30a.

All of the fluid lines are provided with valves so that a control system can be programmed to ensure that the corrected valves open and close in sequence to ensure that the correct operational steps are carried out during forging.

For example, to produce the forging 22 illustrated the rams would all be retracted relative to the die 10 at the commencement of an operating cycle. A billet would be inserted in the central bore 13 of the die 11. Thejack rams are now moved by pressure fluid to bring the die 11 into close proximity with the die 10 during which movement the valve to line 20a would be open to drain and the valve to .line 2012 would be connected to pre-flll supply. When the die 11 is positioned close to the die 10 the main ram 14 is then advanced towards the die 10 by fluid entering the cylinder through line 20b at the same time ram 23 is advanced by fluid pumped to the cylinder 25 via line 25b; line 25a being open to drain. As the forging operation proceeds the ejector ram 26 is advanced to enter into the workpiece to produce a blind hole in the central portion of the billet, retraction of this ram being prevented by the stop member 30 being located over the hole 29. The ejector ram 26 is thus effectively solid with the bolster 17. As the forging continues the jack ram fluid supply lines are opened to drain. At the termination offorging the main ram cylinder is opened to pump via line 20a and to drain via line 20b and the second ram cylinder is also opened to pump via line 25a and drain via line 25b. As the main ram and the second ram are retracted simultaneously the forging is ejected by the ejector ram 26 and when ejection is completed the stop member moves and the ejector ram is retracted due to line 28a being open to pump and line 28b to drain.

The cycle can now be repeated.

Whilst it is very convenient for the jack rams 18 to be located as shown in FIG. 1 and various other figures of the drawing since they then perform the function of providing resistance to rotation of the die 11 they can be replaced by a single jack ram inside the main ram and surrounding the second ram but in this case other means for preventing rotation of the die 11 must be provided.

Since many parts of the arrangements of FIGS. 2, 3 and 4 correspond to those of FIG. 1 like reference numerals will be used on these figures to indicate like parts and only the Modification will be referred to. Thus in FIG. 2 it can be seen that a second ram 123 is located in a cylinder 124 located wholly within the main ram 14. In this case the ejector ram 26 and its cylinder 28 is constructed and arranged as in FIG. 1 and the operating cycle is the same as that of the arrangement of FIG. 1 for producing the forging 22. The fluid supply lines to cylinder 124, that is lines 124a and 1241) pass, in this case through the flange 15 to their respective pumps.

Referring now to FIG. 3, which shows, on a larger scale a more detailed view of part of the arrangement of FIG. 2 it will be seen that the die 11 is secured to the flanged end 15 of the main ram 14. The second ram 123 is provided at its end remote from the piston 24 with a frusto conical bore 124 into which seats a correspondingly shaped spigot 125 formed at one side of a flange 126 adapted to seat on the end of the ram 123 and extending from this flange 126 is a head 127. The main ram 14 is provided with a stepped bore 128 at the end remote from the flange 15 and the piston 24 seats in this bore which is closed by an end plate 129 having a bore therethrough to accommodate the ejector ram 26 which latter is also provided with a head piece 130 removably secured thereto. The head pieces 127 and 130 are produced from hardened steel to enable them to resist wear and since they are removable they can relatively easily be replaced after a period of use.

Referring now to FIG. 4 it can be seen that both a second ram 200 and an ejector ram 201 may have their respective cylinders 202 and 203 and pistons 204 and 205 within the main ram 14. In this case the ejector ram piston 205 is again provided with a stem adapted to cooperate with a stop member 30.

Fluid supply lines for the cylinders 202 and 203 are in this case provided by boring the main ram 14 from its flanged end 15.

In all of the arrangements so far described the rams are preferably vertically disposed with the die 11 located below, and movable upwardly towards the die 10 which performs a circular rocking motion. It is however possible to arrange these rams in the horizontal plane if desired.

Referring now to FIG. 5 it will be seen that it is advantageous in certain cases to arrange for the machine to operate in the horizontal plane. This is the case particularly where the machine is adapted for use in upsetting and forging operations on bar or tube stock.

As shown in FIG. 5 there is provided a fixed cross head 210 in which is located a die 211a adapted to perform a circular rocking motion about a horizontal axis 211. This axis is extensive with a central axis of a die 212 fixed in a second cross head 213. The cross head 213 is slidably mounted on guides 214 and the cross head 213 is bored to receive a wear resistant sleeve 215 of hollow form. The die 212 is bored centrally to a shape corresponding to the shape of the bore of the sleeve 215. The sleeve 215 is removable from the cross head to allow for changes to be made. For example the sleeve 215 may have a circular base to receive circular cross sectioned stock or it may be bored to other shapes to receive stock of cross sections other than circular.

Also mounted on the guides 214 is a ram cross head 216 which may be positionally adjusted relative to the cross heads 210 and 213 so that stock of various lengths may be positioned in the bore of the sleeve 215 and die 212. Within the cross head 216 is a main ram 217 which is hollow and accommodates therein a second ram 218. The main ram 217 serves in use to move the cross head 213 towards the cross head 210 to position the dies 211a and 212 in close proximity and the ram 218 is then adapted to move to push the stock forwardly towards the die 211a to enable material of the stock to be gathered or upset. When sufficient material has been gathered the main ram 217 moves the cross head 213, and thus the die 212, closer to the die 211a to enable the gathered material to be forged to the requisite shape between the dies. At the termination of forging the main ram 217 and second ram 218 are withdrawn and the cross head 216 is retracted to enable the cross head 213 to be retracted for a sufficient distance from the cross head 210 to enable the stock to be removed from the sleeve 215 and die 212. Thus operation is conveniently carried out by moving the second ram forwardly to eject the stock from the sleeve. Clearly this operation whilst feasible is relatively slow due to the fact that loading of the stock, upsetting and forging and ejection are all carried out with the axes 211 of the die 211a the bore of the cross head 213 and the main and second rams in alignment and thus it is desirable to be able to move at least the cross head 213 out of line with the die 211a and the main and second rams so that it can be ejected.

There are several alternatives available for increasing the rate of production from the machine and one of these is schematically illustrated in FIG. 6. In this arrangement the cross head 213 is duplicated, there being one cross head 213 on one guide 214 and a second cross head 213a on a second guide 214a. In this arrangement each cross head is rotatable about its corresponding guide so that, for example, when the cross head 213 is positioned with the axis of its sleeve coextensive with the axis 211 of the die 211a and main and second rams 217 and 218 the cross head 213a is positioned clear of the machine and can be loaded with stock. When an upsetting and forging operation on the stock in cross head 213 is completed it is pivoted to the position shown in FIG. 6 and the cross head 213a is pivoted into its operative position from the combined loading and ejection position as shown. During upsetting and forging of the stock in cross head 213a the forged stock is ejected from cross head 213 (Preferably by an ejector ram) and a new piece of stock is loaded. The cycle can now be repeated.

The directions of movement of the cross heads 213 and 213a is indicated by the arrows A on the drawing.

It is possible to provide three cross heads in this arrangement in which case one would be in the forging and upsetting position, whilst a second is in the loading position, and the third is in the ejection position.

In the schematic layout shown in FIG. 7 a single cross head 220 is provided, in this case there are three operating stations for the cross head. The cross head 220 of this arrangement is provided with three dies 221 and 222 and 223 at 120 spacing and these dies are adapted, by rotation of the cross head 220 to be brought successively into position in alignment with the die 211a which latter, in the drawing has located in alignment therewith the die 221. The cross head 220 rotates about the axis 224 of a guide. Assuming the direction of rotation to be as shown by the arrow B the die 223 is at a loading station and the die 222 is at an ejection station. If the direction of rotation of the cross head were reversed then the die 223 would be at the ejection station and the die 222 at the loading station. In this arrangement there would be an ejector ram at the ejection station.

The schematic layout of FIG. 8 is somewhat more complex than the preceeding arrangements in that there are four stations for a rotary cross head 250 (having four dies) which rotates about the axis 251 of a guide. In addition, there are two dies 252 and 252a adapted to perform a circular rocking motion. The die 252a is adapted to perform an upsetting action and aligned with this die is a main and second ram arrangement similar to that of FIG. 5. At this station a piece of stock is worked on to gather material for forging and when this operation is completed the cross head 250 is indexed through to bring the upset stock into alignment with the die 252 which, in conjunction with a further main and second ram assembly similar to that of FIG. 5 serves to enable forging to be carried out. At the end of the forging operation the cross head 250 is indexed through 90 to bring the forged stock to an ejection station 253 at which is located an ejection ram. The cross head can now be indexed through a further 90 to bring the now empty die to a loading station 254. Clearly in this arrangement whilst a piece of stock is being forged a further piece is being upset and ejection and loading operations are being carried out. The direction of rotation of the cross head is assumed to be as shown by the arrow C. If the direction of rotation is reversed then the die 252 becomes the upsetting die, the die 252a becomes the forging die and the station 253 and 254 become respectively the loading and ejection stations.

Whilst the schemes described with relation to FIGS.

6 to 8 have been related to the arrangement of FIG. 5 they could also be used in relation to any one of the arrangements of FIGS. 1 to 4 in which case more than one main and second ram assembly would be located in a bolster 17 and the latter would be arranged to be moved in either an arcuate reciprocatory manner or in a rotary manner.

It is also possible to arrange for movement of the bolster or the cross head in a reciprocatory manner in a straight line thereby to provide a loading station, an operating station for both upsetting and forging, and an ejection station. In this case the loading station when the bolster or cross head is moving in one direction becomes an ejection station when the bolster or cross head is moving in the reverse direction. Similarly the ejection station becomes a loading station alternatively as the bolster moves first in one direction and then the other.

We claim:

1. In an upsetting or forging machine, at least one pair of relatively movable dies comprising a die adapted to carry out a circular rocking motion about a point related to the centre of said dies, a workpiece receiving die of unitary construction, a mounting for said workpiece receiving die, means to move said mounting linearly towards and away from said die adapted to carry out said circular rocking motion, a through bore in said workpiece receiving die, a bore in said mounting extending co-axially with said bore in said workpiece receiving die, said bores being adapted to receive a bar or tube stock workpiece and means for advancing said workpiece as upsetting or forging takes place.

2. In an upsetting or forging machine as set forth in claim 1, said means for moving said mounting for said workpiece receiving die comprises hydraulic ram means and said means for moving said workpiece relative to said die during upsetting or forging comprises hydraulic ram means (thereby to enable workpiece material to be collected for upsetting or forging).

3. In an upsetting or forging machine as set forth in claim 1 said means adapted to move said mounting and thus said workpiece receiving die, including a hollow cylindrical member.

4. In an upsetting or forging machine as set forth in claim 2 pneumatic means for moving said workpiece relative to said workpiece receiving die as upsetting or forging takes place.

5. In an upsetting or forging machine as set forth in claim 1, mandrel means adapted to be inserted into a tubular form workpiece, means for advancing said mandrel into said tubular form workpiece, said means being advancable with said workpiece as upsetting or forging takes place thereby to prevent deformation of said tubular form workpiece except in the region in which upsetting or forging is taking place.

6. In an upsetting or forging machine at least one die adapted to carry out a circular rocking motion about a part related to the centre of said die, a plurality of workpiece receiving dies, a housing for each of said workpiece receiving dies, means associated with each workpiece receiving die for moving same towards and away from said die adapted to carry out a circular rocking motion, means for moving said workpiece receiving dies angularly and sequentially into a position in which upsetting or forging of a workpiece in a workpiece receiving die can be carried out between said workpiece receiving die and said die adapted to carry out said circular rocking motion, and means for moving said workpiece receiving dies angularly and sequentially into a position remote from said die adapted to carry out said circular rocking motion and, workpiece ejection means being located at said position remote from said die adapted to carry out said circular rocking motion.

7. In an upsetting or forging machine as set forth in claim 6 only a single die adapted to carry out a circular rocking motion about a point related to the centre of said die, four workpiece receiving dies, a housing for each of said workpiece receiving dies, means for moving said housings, and thus said workpiece receiving dies, intermittently in a rotary sense to present each workpiece receiving die sequentially to said die adapted to carry out said circular rocking motion, and workpiece ejection means at a position remote from said die adapted to carry out said circular rocking motion, whereby said workpiece receiving dies may be presented during said intermittent rotary movement sequentially to said workpiece ejection means.

8. In an upsetting or forging machine as set forth in claim 6, each workpiece receiving die being of unitary construction, a control element for carrying each workpiece receiving die, means for advancing said one die towards each workpiece receiving die whilst circular rocking motion is taking place, and means associated with each workpiece receiving die adapted to advance a workpiece as upsetting or forging takes place.

9. In an upsetting or forging machine at least two dies adapted to carry out a circular rocking motion each about a point related to their respective centres, a carrier for said dies, means for indexing said carrier, at least one workpiece receiving die, said indexing means being adapted to bring a die adapted to carry out said circular rocking motion into an operative position relative to a workpiece receiving die.

10. In an upsetting or forging machine as set forth in claim 9 means for moving said dies adapted to carry out said circular rocking motion towards and away from said workpiece receiving die. 

1. In an upsetting or forging machine, at least one pair of relatively movable dies comprising a die adapted to carry out a circular rocking motion about a point related to the centre of said dies, a workpiece receiving die of unitary construction, a mounting for said workpiece receiving die, means to move said mounting linearly towards and away from said die adapted to carry out said circular rocking motion, a through bore in said workpiece receiving die, a bore in said mounting extending coaxially with said bore in said workpiece receiving die, said bores being adapted to receive a bar or tube stock workpiece and means for advancing said workpiece as upsetting or forging takes place.
 2. In an upsetting or forging machine as set forth in claim 1, said means for moving said mounting for said workpiece receiving die comprises hydraulic ram means and said means for moving said workpiece relative to said die during upsetting or forging comprises hydraulic ram means (thereby to enable workpiece material to be collected for upsetting or forging).
 3. In an upsetting or forging machine as set forth in claim 1 said means adapted to move said mounting and thus said workpiece receiving die, including a hollow cylindrical member.
 4. In an upsetting or forging machine as set forth in claim 2 pneumatic means for moving said workpiece relative to said workpiece receiving die as upsetting or forging takes place.
 5. In an upsetting or forging machine as set forth in claim 1, mandrel means adapted to be inserted into a tubular form workpiece, means for advancing said mandrel into said tubular form workpiece, said means being advancable with said workpiece as upsetting or forging takes place thereby to prevent deformation of said tubular form workpiece except in the region in which upsetting or forging is taking place.
 6. In an upsetting or forging machine at least one die adapted to carry out a circular rocking motion about a part related to the centre of said die, a plurality of workpiece receiving dies, a housing for each of said workpiece receiving dies, means associated with each workpiece receiving die for moving same towards and away from said die adapted to carry out a circular rocking motion, means for moving said workpiece receiving dies angularly and sequentially into a position in which upsetting or forging of a workpiece in a workpiece receiving die can be carried out between said workpiece receiving die and said die adapted to carry out said circular rocking motion, and means for moving said workpiece receiving dies angularly and sequentially into a position remote from said die adapted to carry out said circular rocking motion and, workpiece ejection means being located at said position remote from said die adapted to carry out said circular rocking motion.
 7. In an upsetting or forging machine as set forth in claim 6 only a single die adapted to carry out a circular rocking motion about a point related to the centre of said die, four workpiece receiving dies, a housing for each of said workpiece receiving dies, means for moving said housings, and thus said workpiece receiving dies, intermittently in a rotary sense to present each workpiece receiving die sequentially to said die adapted to carry out said circular rocking motion, and workpiece ejection means at a position remote from said die adapted to carry out said circular rocking motion, whereby said workpiece receiving dies may be presented during said intermittent rotary movement sequentially to said workpiece ejection means.
 8. In an upsetting or forging machine as set forth in claim 6, each workpiece receiving die being of unitary construction, a control element for carrying each workpiece receiving die, means for advancing said one die towards each workpiece receiving die whilst circular rocking motion is taking place, and means associated with each workpiece receiving die adapted to advance a workpiece as upsetting or forging takes place.
 9. In an upsetting or forging machine at least two dies adapted to carry out a circular rocking motion each about a point related to their respective centres, a carrier for said dies, means for indexing said carrier, at least one workpiece receiving die, said indexing means being adapted to bring a die adapted to carry out said circular rocking motion into an operative position relative to a workpiece receiving die.
 10. In an upsetting or forging machine as set forth in claim 9 means for moving said dies adapted to carry out said circular rocking motion towards and away from said workpiece receiving die. 